Search PubMed⌕ Search

Biomedical subjects

J R Meyer-Arendt

Publications and source records attributed to J R Meyer-Arendt.

11 recordsLinked to original sources
PubMed1991

Visual acuity degradation resulting from dispersion in polycarbonate.

Visual acuities (VA) were measured through a series of prisms in order to quantify the blur that results from dispersion in polycarbonate. The mean VA of 40 eyes was reduced from a starting level of 20/13 unaided to 20/31 through 16 prism diopters of polycarbonate. The decline was a linear function of prismatic power. The blurring effect of polycarbonate was significantly greater than that of CR39. The blur from polycarbonate was found to be great enough that it should be taken into account whenever polycarbonate is considered for spectacle lenses. A graphical display is provided which can be used by the clinician to predict the degree of blur from a known polycarbonate lens.

Adult↗
PubMed1981

Evaluation of ophthalmic spectacle lenses using the Hartmann test.

Imaging qualities of ophthalmic spectacle lenses can be evaluated by means of the Hartmann Test. This test has traditionally been used to evaluate the lenses and mirrors used in astronomical telescopes. The test involves physical ray tracing of selected light beams and photographic sampling of those beams at planes removed from the Gaussian focus. Certain well-known progressive addition lenses have been found to show characteristic Hartmann dot patterns by which these lenses may be identified. This is of interest to the practicing optometrist for ready identification of such lenses worn by patients.

Eyeglasses↗